Sequence capture phylogenomics of historical ethanol-preserved museum specimens: unlocking the rest of the vault

Natural history collections play a crucial role in biodiversity research and museum specimens are increasingly being incorporated into modern genetics-based studies. Sequence capture methods have proven incredibly useful for phylogenomics, providing the additional ability to sequence historical museum specimens with highly degraded DNA, which until recently have been deemed less valuable for genetic work. The successful sequencing of ultraconserved elements (UCEs) from historical museum specimens has been demonstrated on multiple tissue types including dried bird skins, formalin-fixed squamates, and pinned insects. However, no study has thoroughly demonstrated this approach for historical ethanol-preserved museum specimens. Alongside sequencing of “fresh” specimens preserved in >95% ethanol and stored at -80 ºC, we used extraction techniques specifically designed for degraded DNA coupled with sequence capture protocols to sequence UCEs from historical museum specimens preserved in 70...自然历史馆藏（natural history collections）在生物多样性研究中发挥着关键作用，而博物馆标本也正日益被纳入基于现代遗传学的研究当中。序列捕获（sequence capture）技术已被证实在系统发育基因组学（phylogenomics）领域极具应用价值，其额外优势在于可对DNA高度降解的历史博物馆标本进行测序；而直到不久前，这类标本在遗传学研究中仍被认为价值有限。此前已有研究证实，可从多种组织类型的历史博物馆标本中测序得到超保守元件（ultraconserved elements, UCEs），涵盖干燥鸟类皮肤、福尔马林固定的有鳞类动物标本以及针插昆虫标本。然而，目前尚无研究能够全面证实该方法可应用于乙醇保存的历史博物馆标本。本研究在对保存在体积分数＞95%乙醇中并置于-80℃冰箱保存的‘新鲜’标本开展测序的同时，采用专为降解DNA开发的提取技术结合序列捕获流程，对保存在70%……的历史博物馆标本进行UCE测序。